Ping for https://gcc.gnu.org/pipermail/gcc-patches/2024-August/660958.html
On Wed, Aug 21, 2024 at 09:41:31AM +1000, Nathaniel Shead wrote:
> Bootstrapped and regtested on x86_64-pc-linux-gnu, OK for trunk?
>
> -- >8 --
>
> When compiling with '-fdeclone-ctor-dtor' (enabled by default with -Os),
> we run into issues where we don't correctly emit the underlying
> functions. We also need to ensure that COMDAT constructors are marked
> as such before 'maybe_clone_body' attempts to propagate COMDAT groups to
> the new thunks.
>
> gcc/cp/ChangeLog:
>
> * module.cc (post_load_processing): Mark COMDAT as needed, emit
> declarations if maybe_clone_body fails.
>
> gcc/testsuite/ChangeLog:
>
> * g++.dg/modules/clone-2_a.C: New test.
> * g++.dg/modules/clone-2_b.C: New test.
> * g++.dg/modules/clone-3_a.C: New test.
> * g++.dg/modules/clone-3_b.C: New test.
>
> Signed-off-by: Nathaniel Shead <nathanielosh...@gmail.com>
> ---
> gcc/cp/module.cc | 20 ++++++++++++++++----
> gcc/testsuite/g++.dg/modules/clone-2_a.C | 7 +++++++
> gcc/testsuite/g++.dg/modules/clone-2_b.C | 5 +++++
> gcc/testsuite/g++.dg/modules/clone-3_a.C | 9 +++++++++
> gcc/testsuite/g++.dg/modules/clone-3_b.C | 8 ++++++++
> 5 files changed, 45 insertions(+), 4 deletions(-)
> create mode 100644 gcc/testsuite/g++.dg/modules/clone-2_a.C
> create mode 100644 gcc/testsuite/g++.dg/modules/clone-2_b.C
> create mode 100644 gcc/testsuite/g++.dg/modules/clone-3_a.C
> create mode 100644 gcc/testsuite/g++.dg/modules/clone-3_b.C
>
> diff --git a/gcc/cp/module.cc b/gcc/cp/module.cc
> index 5cd4f313933..9a9c0fdfe81 100644
> --- a/gcc/cp/module.cc
> +++ b/gcc/cp/module.cc
> @@ -17948,10 +17948,22 @@ post_load_processing ()
> dump () && dump ("Post-load processing of %N", decl);
>
> gcc_checking_assert (DECL_MAYBE_IN_CHARGE_CDTOR_P (decl));
> - /* Cloning can cause loading -- specifically operator delete for
> - the deleting dtor. */
> - if (!TREE_ASM_WRITTEN (decl) && maybe_clone_body (decl))
> - TREE_ASM_WRITTEN (decl) = 1;
> +
> + if (DECL_COMDAT (decl))
> + comdat_linkage (decl);
> + if (!TREE_ASM_WRITTEN (decl))
> + {
> + /* Cloning can cause loading -- specifically operator delete for
> + the deleting dtor. */
> + if (maybe_clone_body (decl))
> + TREE_ASM_WRITTEN (decl) = 1;
> + else
> + {
> + /* We didn't clone the cdtor, make sure we emit it. */
> + note_vague_linkage_fn (decl);
> + cgraph_node::finalize_function (decl, true);
> + }
> + }
> }
>
> cfun = old_cfun;
> diff --git a/gcc/testsuite/g++.dg/modules/clone-2_a.C
> b/gcc/testsuite/g++.dg/modules/clone-2_a.C
> new file mode 100644
> index 00000000000..47e21581fdc
> --- /dev/null
> +++ b/gcc/testsuite/g++.dg/modules/clone-2_a.C
> @@ -0,0 +1,7 @@
> +// { dg-additional-options "-fmodules-ts -fdeclone-ctor-dtor" }
> +// { dg-module-cmi M }
> +
> +export module M;
> +export struct S {
> + inline S(int) {}
> +};
> diff --git a/gcc/testsuite/g++.dg/modules/clone-2_b.C
> b/gcc/testsuite/g++.dg/modules/clone-2_b.C
> new file mode 100644
> index 00000000000..80c1e149518
> --- /dev/null
> +++ b/gcc/testsuite/g++.dg/modules/clone-2_b.C
> @@ -0,0 +1,5 @@
> +// { dg-additional-options "-fmodules-ts -fdeclone-ctor-dtor" }
> +
> +import M;
> +
> +S s(0);
> diff --git a/gcc/testsuite/g++.dg/modules/clone-3_a.C
> b/gcc/testsuite/g++.dg/modules/clone-3_a.C
> new file mode 100644
> index 00000000000..87de746f5c2
> --- /dev/null
> +++ b/gcc/testsuite/g++.dg/modules/clone-3_a.C
> @@ -0,0 +1,9 @@
> +// { dg-additional-options "-fmodules-ts -fdeclone-ctor-dtor" }
> +// { dg-module-cmi M }
> +
> +export module M;
> +
> +struct A {};
> +export struct B : virtual A {
> + inline B (int) {}
> +};
> diff --git a/gcc/testsuite/g++.dg/modules/clone-3_b.C
> b/gcc/testsuite/g++.dg/modules/clone-3_b.C
> new file mode 100644
> index 00000000000..23c9ac4a804
> --- /dev/null
> +++ b/gcc/testsuite/g++.dg/modules/clone-3_b.C
> @@ -0,0 +1,8 @@
> +// { dg-module-do link }
> +// { dg-additional-options "-fmodules-ts -fdeclone-ctor-dtor" }
> +
> +import M;
> +
> +int main() {
> + B b(0);
> +}
> --
> 2.43.2
>
